This is a prepped and cleaned/drilled kit for 7/8 hiems for CAT EYE style Duramax’s (may fit others but I have only test fit the kit on the CAT EYE style) this kit is in welded. Cut from .250” mild steel plate. Keyed holes for easy alignment and extra strength. Allows the use of factory length u bolts. Can be bolted or welded on at the frame. The front mounts shape is to allow clearance of certain cross members if it is installed in that location.